<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>app1</title>
</head>
<style>
  h1 {
    color: aquamarine;
  }
</style>

<body>
  <h1>app1</h1>
  <button id="app1">100</button>
  <script src="./app2.js"></script>
  <script src="https://cdn.bootcdn.net/ajax/libs/lodash.js/4.17.21/lodash.core.js"></script>
</body>
<script>
  console.log('app1 哈哈');
  console.log(_.max([1, 2, 3]));
</script>

</html>